Animal Surgeries

10 Wild Animal Surgeries You Didn't Even Know Were Possible

Recently, I toured two facilities on the California coast that rescue marine animals: The Marine Mammal Center in Sausalito and International Bird Rescue in Los Angeles. The trip was sponsored by Procter & Gamble, which has been donating its Dawn dishwashing liquid to both organizations for over 30 years. For both organizations, Dawn is the preferred agent to clean oil off of animals, and has saved over 75,000 animal lives over the past 30 years. While oil removal may be one of the more standard procedures, both centers perform daring surgeries on injured animals with the goal of releasing them back into the wild. Unlike surgeries on humans or household pets, wild animals present unique challenges, often because the surgeries are rare or have never been tried. There is no surgical manual for these animals, and veterinarians must be skilled at developing surgical plans — all while keeping the animals wild and not habituated to human contact.

I interviewed three veterinarians who described some of their most memorable surgeries on wild animals: Dr. Shawn Johnson, the Director of Veterinary Science at The Marine Mammal Center; Dr. Rebecca Duerr, Research Director and Veterinarian at International Bird Rescue; and Dr. Rebecca Greene, who was previously an Associate Veterinarian at The Marine Mammal Center.

Northern elephant seal, cataract surgery

In the past few years, The Marine Mammal Center has had two cases where an elephant seal came in with impaired vision from cataracts in both eyes. Cataracts can be congenital, a hereditary defect, or can be caused by trauma, infection, or malnutrition. In both cases, veterinarians were able to remove the cataracts, restoring vision to the seals.

Northern elephant seal, cataract surgery (continued)

The Marine Mammal Center

Dr. Shawn Johnson: “It’s a life or death situation. If we can’t get vision back in at least one eye, then we’ll be unable to release the animal, and unfortunately we’d have to put it down. We work with a veterinary ophthalmologist to do the surgery, because this is a real specialty. It’s about a two-hour surgery per eye. The surgeon will go in, basically do a 180-degree cut of the cornea, fold it back, and with a little spoon-like instrument, pop the lens out of the eye and suture the cornea back on. Usually within 24 hours, the animals are opening their eyes, looking around, and seeing the world as it is. By four or five weeks they can go in the water full time. Then we test them with some live fish in their pool and make sure they can track the fish in the water and catch it. Once they accomplish that task, they’re ready to be released. Cappy — one of the elephant seals with cataracts — had a successful surgery and was released. A few months later, we were out working on a research project and we actually saw him out on the beach. He was able to catch fish, see, and basically thrive.”

Brown pelican, pouch laceration

International Bird Rescue

In June 2014, a brown pelican was brought to International Bird Rescue with a human-caused laceration that severed its entire pouch, a crime that motivated the U.S. Fish and Wildlife Service to offer a $20,000 reward for information leading to the arrest of the culprit. The cut was so severe that staff initially wondered if the animal would need to be euthanized, but veterinarian Dr. Rebecca Duerr expected it could be released back into the wild with surgery. The pouch was initially closed with surgical staples so the pelican, which was later named Pink, could eat and gain strength before the lengthy operation to suture the pouch back together.

Brown pelican, pouch laceration (continued)

International Bird Rescue

Dr. Rebecca Duerr: “Pelican pouch skin is kind of an odd structure. It’s about a millimetre thick, but it essentially has outside skin on both sides and muscle down the middle. I split it the long way into an inner and outer layer, then fold the inside layers together on the inside and the outside layers together on the outside, so it’s literally suturing it in two different layers. The cut went back to its ear, so it was actually longer than the bill. It was about 45 cm on a side. Twice on each side is 180 cm, so it was about 2 m of suturing.

Brown pelican, pouch laceration (2)

International Bird Rescue

The sutures end up having to be about 3 mm apart, so it is time consuming and tedious — but it’s a very Zen activity. We did the first half, gave him a day off so he could eat, then did the second half. It was completely healed by 11 and 13 days after the suture placement, so it healed really fast. The bird got released, and flew off with some fanfare — there were a lot of people rooting for that animal.”

Hawaiian Monk Seal, hook lodged in esophagus

The Marine Mammal Center

The Marine Mammal Center recently opened a hospital in Hawaii, the home of the critically endangered Hawaiian monk seal. When one of these seals was found with a fishing hook stuck in its esophagus, Dr. Shawn Johnson, who primarily works at the facility in San Francisco, was called in to assist the veterinary team in Hawaii with the surgery.

Dr. Shawn Johnson: “This monk seal was reported having a fishing line coming out of its mouth. So we rescued the seal and brought him into a veterinary hospital in Oahu. We took x-rays and found a hook caught in the esophagus, about halfway down to the stomach. If the hook perforates the side of the esophagus and the animal gets a nasty infection, it will die. There are only 1,100 Hawaiian monk seals left, so they’re a highly endangered species and every single one of them matters. In surgery, we were able to visualize the hook with an endoscope and insert a de-hooking device. We were being very tentative at first. It’s really scary to know that you can rip the esophagus and that would be it for the monk seal. After about an hour of trying to get the hook out, we said, ‘Let’s put a little muscle behind this and see what happens.’ We were finally able to get the hook to release from the esophagus and pull it out through the mouth. It was a huge relief. The monk seal was held in care for two days to make sure he was okay and then he was released. He gets re-sighted almost every day, so he’s doing well.”

Great blue heron, skin burns from oil

International Bird Rescue

Oil not only inhibits a bird’s ability to fly or swim. It is also caustic, and can burn its skin. A great blue heron had skin burns after getting oiled at a refinery in 2013, and when a large skin wound on its thigh wouldn’t heal, a skin graft was performed.

Great blue heron, skin burns from oil (2)

International Bird Rescue

Dr. Rebecca Duerr: “A lot of refineries have open pit-like structures. They do their best to keep animals out of their hazards, but every now and then they’ll bring us birds that are completely encased in oil. This bird had burns over a huge chunk of its body with big open ulcers everywhere. If a bird has a laceration or a wound where there’s a chunk of skin missing, a lot of times I can close it by using the skin from the surrounding areas and pulling it closed.

Great blue heron, skin burns from oil (3)

International Bird Rescue

But this bird had so much skin affected there just wasn’t enough healthy skin to do anything with. We were managing them all as open wounds for a long time, and many of them were healing well. But there was one very large area on the bird’s thigh that just wouldn’t heal and kept being infected. I ended up taking a skin graft off his neck, which wasn’t really damaged, and stitched it on. That ended up doing the trick — it formed a perfect bandage.”

Sea lion, flipper amputation

The Marine Mammal Center

Fractures and bone infections are fairly common in the animals rescued by The Marine Mammal Center. If a fracture or infection occurs in the hind flipper of a sea lion, sometimes the best course of action is to amputate it.

Sea lion, flipper amputation (2)

The Marine Mammal Center

Dr. Shawn Johnson: “With osteomyelitis — infection of the bone — if you were a dog or a human, you’d be in the hospital with an intravenous catheter getting fluids and really high-powered antibiotics to help treat that infection. Unfortunately, this type of intensive care is not possible with wild animals. So one of our options for treatment is to remove the infection. Sometimes the bone is so infected or damaged that we just remove the whole limb.

Sea lion, flipper amputation (3)

The Marine Mammal Center

We’ve had a couple really interesting cases the last few years when we’ve totally removed a hind flipper of a sea lion. One animal that I remember well is Angie, because she had a great personality. She had a nasty infection in the bone of her hind flipper, so we had to amputate to remove all of the infected part. Sea lions use their front flippers to swim, and their hind flippers are like rudders. So they can get around with just one hind flipper.”

Brown pelican, patagium laceration

International Bird Rescue

Last year, a brown pelican was discovered with a severed patagium — a flap of skin that runs from a bird’s wrist to its shoulder and is essential for flight. Since the goal of International Bird Rescue is to get birds back into the wild, it is crucial that they can fly before they are released. It took 14 months of surgeries and physical therapy before this pelican was healthy enough to be released.

Brown pelican, patagium laceration (2)

International Bird Rescue

Dr. Rebecca Duerr: “This particular bird came in with a fishing line injury where the fishing line had cut into the patagium so that it was cut almost all the way down to the elbow. I had never tried stitching one together, so I thought I’d give it a try. It was really infected with a lot of debris and pus in it, so I stitched the bottom side of the skin together and left the top open so we could do open wound management. That bird had maybe six anaesthetic procedures to deal with that wound, and more wound care when he was awake with bandage changes. Once the wound was healed, we started doing exercises and physical therapy. Limbs that have been immobilized may end up with restrictions in range of motion, and this bird had been in a wing wrap for a long time. We ended up doing a lot of wing extension exercises. He was in care for 14 months — we almost gave up on him a couple of times — but he always seemed to be making really slow progress. If an animal has plateaued, we’re more likely to make the call to euthanize. If they’re making even the tiniest bit of progress, if we can, we’ll keep going.”

Northern elephant seal, herniated stomach

The Marine Mammal Center

Herniated stomachs aren’t altogether uncommon in elephant seals, but usually they are only found after the animal has died and a necropsy is performed. In this case, the herniated stomach was discovered soon enough that the elephant seal had a chance at surviving with a successful operation. After consultation with a number of different surgeons, The Marine Mammal Center elected to do a laparoscopic procedure — a surgery involving small incisions and tiny cameras — to perform the operation. It was the first time a laparoscopic procedure had been used in an elephant seal to fix this type of defect in the diaphragm.

Dr. Rebecca Greene: “The hernia is basically a gap in the diaphragm that separates the chest and abdominal cavities. It allows contents to go where they shouldn't go, which we could see on x-rays. In this case, the end of the esophagus and part of the stomach were slipping into the chest where the heart and lungs are, making it difficult for the seal to breathe, keep food down and gain weight. One way to fix this is to reposition and secure the stomach in the right place. I knew we needed a less invasive approach for this animal, so we decided to go with laparoscopy. After a good dose of sedatives and gas anesthesia, we inserted the laparoscope — a long black instrument with a camera on the end — through the skin on the seal’s belly. The camera allowed us to see inside so we could gently grasp the stomach and pull it back out of the chest cavity and suture it into a more normal position.”

White-faced ibis, radius and ulna fracture

International Bird Rescue

In August 2014, International Bird Rescue received a white-faced ibis that had radius and ulna fractures, possibly from getting hit by a vehicle. It was an especially rare species for the center, which presented some challenges.

Dr. Rebecca Duerr: “Bird wings are put together very similarly to your own arm. One of the problems with radius and ulna fractures is that the bones can fuse together. In order for a bird to fly, it needs to move those bones independently. The best outcome when both those bones are broken is to pin both bones separately, but I had never done it on an ibis before. It was a pretty unusual species for us. A standard technique in birds is to put an intramedullary (IM) pin — a pin down the long way — through the ulna and then two screws perpendicular to the bone. Then, an external fixator is placed combining those two screws with the IM pin. The radius is fixed by inserting a pin down the cavity in the middle. With this ibis, the pins came out in about two weeks; we did about a week of physical therapy, then let the bird go and he flew off nicely.”

Brown pelican, synostosis

International Bird Rescue

In 2012, International Bird Rescue received a brown pelican that had previously broken its wing, and its radius and ulna had fused together during the healing process. The fusion of bones — called synostosis — rendered the bird flightless. To fix the problem, the bones were separated, and some of the bird’s own fat was used as lubrication between them to prevent fusion from recurring.

Dr. Rebecca Duerr: “This bird had come in with a previously healed fracture where the radius and ulna were fused to each other, so the wing couldn’t extend. I had never done this procedure before, but I went in and harvested some fat from his abdomen and then mechanically removed a bunch of the bone that was bonding the two bones together. The trouble is that there is an artery that runs between the radius and the ulna, and this bony bridge between the two bones was wedged right up against that artery. So when I was cutting down on the bottom of it, I could feel the massive pulse of the bird right where I was cutting. It was pretty nerve-wracking surgery, but it went fine. I patched fat in the gap, closed it up, and we did a lot of physical therapy — daily stretching to keep the bones from fusing again. He was in care for nine months before being released.”

Brown pelican, toe amputation

International Bird Rescue

This February, a brown pelican was released after a toe amputation done at International Bird Rescue. Each bird that is released from there has an identification band placed around its leg, and recently this bird was seen in the wild, confirming that the amputation was successful in allowing the bird to survive in its natural habitat.

Dr. Rebecca Duerr: “Pelicans run into problems with their feet all the time, and I often worry, ‘Is it okay to amputate this?’ We have certain rules to work under with the U.S. Fish and Wildlife Service, but we’re allowed to have a lot of judgment on what can be removed based on what species we’re dealing with. Pelicans have what’s called a totipalmate foot where all the toes are webbed together. This bird had a fishing hook injury on its toe, and the toe was infected and needed to be removed. If you take off the whole toe, the webbing with it also needs to go so the bird ends up with kind of a weird looking foot. We ended up with two toes in the front, then no webbing, then a toe in the back. The bird got released in February this year, and was just seen in Oceanside, CA. It’s really nice to have a re-sighting on animals like that.”